RPS6KB1 and esophageal squamous cell carcinoma: Through the results of target screening, in vitro pull-down assays, and in vitro kinase assays, we identified that ethyl ferulate is a potent mTORC1/mTORC2 protein kinase inhibitor that can reduce mTOR/AKT/p70S6K signaling in ESCC cells (Figures 3A, B).